Bournonite
CuPbSbS3IMA symbol: Bnngrandfathered
Bournonite is a sulfide or sulfosalt mineral with the formula CuPbSbS3, crystallizing in the orthorhombic system. It has a Mohs hardness of 2.5-3, typically black or gray in color, with a metallic luster, a specific gravity of 5.7-5.9. Its streak is black or gray.
Photos



Crystallography
| Crystal system | orthorhombic crystal systemWikidata (CC0) |
|---|---|
| Space group | P n 21 m |
| Cell (Å, °) | a = 8.153, b = 8.692, c = 7.793; α = 90, β = 90, γ = 90 |
| Cell volume | 552.258 ų, Z = 4 |
| Axial ratios | 0.9380:1:0.8966calculated from COD 9008197 |
| Source structure | COD 9008197 (Zeitschrift fur Kristallographie, 1970) |
Powder X-ray diffraction (calculated)
| d (Å) | 2.733 | 2.68 | 3.835 | 2.817 | 3.897 | 2.973 |
|---|---|---|---|---|---|---|
| I/I₀ | 100 | 47.8 | 45 | 34.6 | 33.6 | 29.7 |
xrd-v1: CuKa1 1.5406A, 2theta 5-90, top10, Imax=100, no DW/PO. Computed from COD 9008197; idealized occupancies, no preferred orientation.
Physical properties
| Density (calculated) | 5.878 g/cm³calculated from COD 9008197 |
|---|---|
| Hardness (Mohs) | 3single sourceWikidata (CC0) 2.5-3single sourceDana, System of Mineralogy, 6th ed. (1892) |
| Specific gravity | 5.7-5.9 g/cm3corroboratedDana, System of Mineralogy, 6th ed. (1892) |
| Color | black, graysingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Streak | black, graysingle sourceDana, System of Mineralogy, 6th ed. (1892) |
| Luster | metallicsingle sourceDana, System of Mineralogy, 6th ed. (1892) |
Chemistry (calculated)
| Molecular weight | 488.7 g/molcalculated from the IMA formula |
|---|---|
| Composition (wt%) | Cu 13%, Pb 42.4%, Sb 24.92%, S 19.68% |
Classification
| Nickel-Strunz (10th) | 2.GA.50Wikidata (CC0) |
|---|---|
| Nickel-Strunz (9th) | 2.GA.50Wikidata (CC0) |
| Dana (8th) | 3.4.3.2Wikidata (CC0) |